Pipeline accidents and explosions happen, due to large leaks…. ….. small leaks are ubiquitous. Pipelines in US are old!
PHMSA 2009 Transmission Annual Data
Flames consume homes during a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Photo by Ezra Shaw/Getty Images)
Howarth et al. (2012-b) – Background paper for National Climate Assessment
Emissions at well site… shale gas and other unconventional gas
Howarth et al. (2012-b) – Background paper for National Climate Assessment
Direct, landscape scale measurements!!
Time frame for comparing methane and carbon dioxide: • Hayhoe et al. (2002) • Lelieveld et al. (2005) • Jamarillo et al. (2007) • Howarth et al. (2011) • Hughes (2011) • Venkatesh et al. (2011) • Jiang et al. (2011) • Wigley (2011) • Fulton et al. (2011) • Stephenson et al. (2011) • Hultman et al. (2011) • Skone et al. (2011) • Burnham et al. (2011) • Cathles et al. (2012)
0 to 100 years 20 & 100 years 100 years 20 & 100 years 20 & 100 years 100 years 100 years 0 to 100 years 100 years 100 years 100 years 100 years 100 years 100 years
High potential for massive emissions of ancient CH4 due to thawing permafrost and release of “frozen” methane (methane hydrates and clathrates). CH4 CH4 CH4
Zimov et al. (2006) Science
5
Hansen et al. (2007) identified critical threshold in climate system, to avoid melting of natural methane hydrates, leading to runaway positive feedback of global warming = 1.8o C.
Without control of methane and BC, critical thresholds of 1.5o to 2o warming predicted in 15 to 35 years (even with aggressive CO2 control!!)
Shindell et al. 2012 Science
Greenhouse gas footprint of shale gas compared to other fossil fuels (20-year integrated global warming potential for methane)
Howarth & Ingraffea, Nature, 15 September 2011
(Howarth et al. 2012, based on 2011 EPA data for 2009)
Percentage contribution of methane to the total greenhouse gas inventory of the US (2009 data) 20-yr integrated time frame
100-yr integrated time frame
Methane from all sources
44%
19%
Methane from natural gas
17%
7.4%
(Howarth et al. 2012)
Percentage contribution of methane to the total greenhouse gas inventory of the US (2009 data) 20-yr integrated time frame
100-yr integrated time frame
Methane from all sources
44%
19%
Methane from natural gas
17%
7.4%
Shale gas a very small part of gas in 2009… As shale gas increasingly replaces conventional gas, methane emissions will grow! (40% to 60% greater emissions from shale gas). (Howarth et al. 2012)
Can methane emissions be reduced? Yes, but:
-- a lot are purposeful venting (economic decision) -- leakage from old tanks and pipelines would be very expensive to fix. Is it worth the investment for a “transitional fuel?”
-- would require regulation; industry is strongly opposed to regulation, and has a history of getting around regulation when imposed.
Energy Information Agency, U.S. Department of Energy
Break even point (Berman 2010)
Break even point (IEA 2011)
On Feb. 29, 2012 = $2.52 per 103 ft3 http://www.eia.gov/dnav/ng/hist/n9190us3m.htm (downloaded March 1, 2012)
14
Why Is Shale Gas Development “Unconventional”? Why an SGEIS? • Because it requires 4 technologies only recently combined to make gas production from shales technically and economically feasible. • Directional drilling: needed to access a thin layer of shale with long laterals. • High frac fluid volumes: needed to stimulate gas release from many existing fractures. • Slickwater: needed to control the amount of power needed to pump large volumes of frac fluids, at high pressures, quickly, over long distances, through small diameter casing. • Multi-well Pads and Cluster Drilling: needed to access as much of the gas inventory as possible, under constraints of leasing and capital. 15
High Volume, Slickwater Fracing from Long Laterals (HVSFLL): The Concept
Not to scale ~ 5000 ft
Cap rock
The Lateral
Shale Layer Cap rock
~ 100 ft Pay zone 16
Early Joints at Taughannock Falls Gas Producing Shales are Heavily Fractured Naturally
Geneseo-Burket (Devonian black shale) Taughannock Falls State Park, Trumansburg, N.Y.
Photo Courtesy T. Engelder 17
Example of Spatially Intense Development: Dallas/Fort Worth Airport Property, Barnett Shale Play • 53 pads on 18,076 acres, 30 square miles 1 mile
• Each red line is a well lateral
• Each red dot is a pad • Almost complete coverage • Patchwork, mostly ideal units • One leaser, one developer 18
Unconventional Development of Gas from Shale Is New Technology
From NYS SGEIS revised draft, page 5-5, 2011
About ½ of all unconventional shale gas globally produced in the last 3 years 19
How Much Water For Each Well? • Depends on length of lateral, number of frac stages • Typically, much more than 1 million gallons Chesapeake Energy is averaging 5.5 million gallons/well in PA Marcellus play. http://hydraulicfracturing.aitrk.com/Pages/information.aspx
20
What Else Goes Down The Well With The Water? Proppant: Sand or coated ceramic beads, transported into the fractures to keep them open after fracturing pressure release. Gelling Agents: Increase fluid viscosity to help proppant transport. Biocides: Kill bacteria that harm the gelling agents, can sour well. Breakers: Decrease viscosity of the fracturing fluid, after the fracturing process, to improve flowback. Fluid-Loss Additives: Decrease leakoff of fracturing fluid into the rock. Anti-Corrosives: Protect metallic elements in the well. Friction Reducers: Allow high pressures and flow rates. http://www.epa.gov/OGWDW/uic/pdfs/cbmstudy_attach_uic_ch04_hyd_frac_fluids.pdf See Table 6.1 NYS dSGEIS, page 6-19
21
What Comes Back Up? Called FLOWBACK • When the fracturing process is completed, the pressure is released, and much of the fracturing fluid backflows to the wellhead, during the flowback period, and afterwards*. • The backflow will: be highly saline, e.g. sodium and calcium salts; contain some heavy metals, e.g. barium, strontium; contain frac fluid additives; contain NORM, primarily Radium-226 See Table 5.10, NYS dSGEIS, page 5-106
22
Where Does The FLOWBACK Go? Initially, it remains on site, in a collection pit, or tanks. Pit serving a single well
http://www.epa.gov/OGWDW/uic/pdfs/cbmstudy_attach_uic_ch04_hyd_frac_fluids.pdf
23
Where Does The FLOWBACK Go? Pit servicing multiple pads
Where it goes after that is the BIG QUESTION
http://www.donnan.com/Marcellus-Gas_Hickory.htm
24
Flowback Disposal Possibilities • • • • •
EPA-regulated Class II “brine” injection well Sewage treatment plant (POTW) Industrial waste treatment facility Road spreading Recycling/Reuse
25
Gas Is Supposed to Rise Inside the Production Casing, Not Outside
VIDEO of Methane Bubbling At Well Head
26
Bubbling in Muncy Creek, Lycoming County, PA: Example of Migration of Hydrocarbons
Video Courtesy of Ralph Kisberg, Responsible Drilling Alliance 27
GOOD MECHANICAL INTEGRITY CONDUCTOR PIPE FRESH WATER AQUIFER ZONE
SURFACE CASING
PRODUCTION CASING
SHALLOW PRODUCING ZONE
INTERMEDIATE PRODUCING ZONE
28 TARGET PRODUCING ZONE
CEMENT CHANNELING CONDUCTOR PIPE
PRESSURE BUILDS UP
FRESH WATER AQUIFER ZONE
SURFACE CASING
CEMENT
CASING
FORMATION
PRODUCTION CASING
SHALLOW PRODUCING ZONE
INTERMEDIATE PRODUCING ZONE
29 TARGET PRODUCING ZONE
LEAK THROUGH CASING CONDUCTOR PIPE
PRESSURE BUILDS UP
FRESH WATER AQUIFER ZONE
SURFACE CASING
FORMATION
CASING
PRODUCTION CASING
SHALLOW PRODUCING ZONE
INTERMEDIATE PRODUCING ZONE
30 TARGET PRODUCING ZONE
INSUFFICIENT CEMENT COVERAGE CONDUCTOR PIPE
PRESSURE BUILDS UP
FRESH WATER AQUIFER ZONE
SURFACE CASING
PRODUCTION CASING
SHALLOW PRODUCING ZONE
INTERMEDIATE PRODUCING ZONE
31 TARGET PRODUCING ZONE
New Scientific Data on Methane Contamination of Water Wells
www.pnas.org/cgi/doi/10.1073/pnas.1100682108
32
As-Built Casing Layouts for 2 PA Marcellus Wells That Contaminated Water Wells
33
?????
34
Horn River Area, NE British Columbia
35
Encana Says “No!” This One Is It 417 million gallons of water 78,400 tons of sand 8 milllion gallons of fracing chemicals 500 frac intervals 10,000 foot laterals 40,000 hp for fracing pumps
36
Direction of max horizontal stress
Notice NNW-SSE orientation of non-square, about 640 acre, spacing unit. Geology and leasing control.
Footprint of the Best Unit, 7-Well Pad, Pennsylvania
Photos courtesy Robert Donnan
38
Marcellus Well Being “Finished” Outside Dimock, Pa June, 2011: Major Source of Methane Emission
Photo and FLIR Methane-Tuned Video Courtesy Frank Finan
39
Marcellus Well Being “Finished” Outside Dimock, Pa. June, 2011: Major Source of Methane Emission
Video
Video courtesy of Frank Finan 40
Ancillary Infrastructure Is Major Source of Methane Emission
Courtesy of Calvin Tillman.
41
Natural Gas Leaks in and Around Boston: Pipelines A Major Source of Methane Emission
Courtesy of Prof. Nathan Phillips, Boston University
Where Can You Find Reliable Information?
http://www.psehealthyenergy.org/
43
Where Can You Find Reliable Information?
http://www.earthworksaction.org/oil_and_gas.cfm
44
MIT Study On Economics of Shale Gas
Jacoby et al., Economics of Energy & Environmental Policy, Vol. 1, No. 1, pp. 37-51, 2011
45
46
